|Van Emon, M|
Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/1/2010
Publication Date: 9/1/2010
Citation: Horn, M.J., Van Emon, M.L., Gunn, P.J., Eicher, S.D., Lemenager, R.P., Pyatt, N., Lake, S.L. 2010. The Effects of Maternal Natural (RRR Alpha-Tocopherol Acetate) or Synthetic (All-Rac Alpha-Tocopherol Acetate) Vitamin E Supplementation on Suckling Calf Performance, Colostrum IgG, and Immune Function. Journal of Animal Science. 88:3128-3135. Interpretive Summary: The objective of this study was to determine the effects of maternally supplemented natural- or synthetic-source vitamin E on suckling calf performance and immune response. Calves suckling cows supplemented with natural- and synthetic-source vitamin E had increased circulating concentrations of vitamin E at 24 h which appeared to continue throughout maternal supplementation; however, calf immune responses increased over time but performance(growth) was not affected by the treatments. A treatment × day interaction existed in response to OVA antigen (measuring antibody response to egg albumin) where NAT calves had a greater response than SYN calves at d 63. Nodule size to an OVA subcutaneous injection (cell-mediated immune measure) at 65 d of age was not affected by maternal dietary supplementation. This verified that it was an antibody rather than a cellular response that was affected by the treatments. These results establish that supplementation of either form of alpha-tocopherol to the dam is beneficial for the calf and that a further benefit for enhanced antibody production may occur with the natural form compared with the synthetic form. These results will be useful information for producers needing to enhance adaptive immunity of calves early in life.
Technical Abstract: The objective of this study was to determine the effects of maternally supplemented natural- or synthetic-source vitamin E on suckling calf performance and immune response. In a two-year study, 152 two- and three-year old spring-calving Angus-cross beef cows were blocked by age, BW, and BCS into one of three isocaloric, corn-based dietary supplements containing 1) no additional vitamin E (CON), 2) 1000 IU/d synthetic-source vitamin E (SYN), or 3) 1000 IU/d natural-source vitamin E (NAT). Maternal supplementation began approximately 6 wk prepartum and continued until the breeding season. Colostrum from cows and blood from calves was collected 24 h postpartum for analysis of IgG concentration as an indicator of passive transfer and circulating vitamin E (alpha-tocopherol) concentration. At 19 d of age, blood was collected from calves to determine the expression of CD14 and CD18 molecules on leukocytes. At 21 and 35 d of age, calves were injected subcutaneously in the neck with hen egg albumin (20 mg; OVA) and bled weekly until d 63 of age to determine total antibodies produced to OVA. At d 63 of age, calves were administered an intradermal injection of OVA (1 mg) in the neck to assess cell-mediated immunity which was determined on d 65 of age by measuring nodule size with calipers. Circulating alpha-tocopherol concentrations were increased at both 24 h (P = 0.001) and at the day of initial OVA challenge (P < 0.001) in SYN and NAT compared with CON calves. No differences were detected (P > 0.05) for calf birthweight, ADG, or weaning weight. There were no differences (P > 0.05) in calf serum circulating IgG or cow colostrum IgG at 24 h or presence of CD14 and CD18 molecules at d 19 of age. A treatment × day interaction (P = 0.01) existed in response to OVA antigen where NAT calves had a greater response than SYN calves at d 63. Nodule size at 65 d of age was not affected (P = 0.92) by maternal dietary supplementation. In conclusion, calves suckling cows supplemented with natural- and synthetic-source vitamin E had increased circulating concentrations of a-tocopherol at 24 h which appeared to continue throughout maternal supplementation; however, calf immune function and performance were not affected. These reults indicate a benefit for increasing blood alpha-tocopherol concentrations by supplementing both natural and synthetic forms of alpha-tocopherol to the cows, and a potential for improved d 63 antibody responses by supplementing with the natural form and will be useful information for producers needing to enhance immunity of calves earlier in life.